New approach to antibacterial treatment of cotton fabric with silver nanoparticle–doped silica using sol–gel process

In this study, cotton fabric was successfully modified to have an antibacterial property through use of the sol–gel process. Dodecanethiol‐capped silver nanoparticles, which have powerful antibacterial activity, were incorporated in silica sol. The starting materials were silver nitrate, tetraoctylammonium bromide, sodium borohydride, chloroform, 1‐dodecanethiol, ethanol, tetraethylorthosilicate, and water. The cotton fabric was padded with dodecanethiol‐capped silver nanoparticle–doped sol, dried at 60°C, and cured at 150°C. Scanning electron microscopy showed a uniform and continuous layer of doped sol on the fiber surface. The antibacterial effects of the treated cotton fabric against Escherichia coli were examined and found to be excellent. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101:2938–2943, 2006     

Fabrication of superhydrophobic fabric coating using microphase‐separated dodecafluoroheptyl‐containing polyacrylate and nanosilica

Superhydrophobic coating was developed on cotton fabric in this article using a dodecafluoroheptyl‐containing polyacrylate (DFPA) and nanosilica. Film morphology of DFPA on cotton fibers/fabrics and chemical compositions of the treated cotton fabric were investigated using scanning electron microscopy (SEM), atomic force microscopy (AFM), and X‐ray photoelectron spectroscopy (XPS), respectively. DFPA could form a relatively even film on the cotton fabric/fiber under SEM observation; however, it presented a rough and microphase‐separated pattern under AFM observation. There were many mountain‐like protuberances. The height of the protuberances and the root mean square roughness (R_ms) of the film reached about 20–50 nm and 12.511 nm in 2 × 2‐μm² scanning field (as the scale data was 100 nm). XPS analysis indicated that the perfluoroalkyl groups had the tendency to enrich at the film–air interface. DFPA could make the treated cotton fabric with a water contact angle (WCA) at about 138.5°. Cotton fabric was previously roughened using a 1 wt % silica sol with an average particle size of 20–30 nm and then finished by DFPA; hydrophobicity of the resultant cotton fabric was strongly improved, and WCA could reach 153.6°. The color of this superhydrophobic fabric would not be influenced, but its softness decreased compared to untreated fabric. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis of Silica Nanoparticles by Ultrasound‐Assisted Sol‐Gel Method: Optimized by Taguchi Robust Design

Silica nanoparticles were prepared by ultrasound‐assisted and conventional sol‐gel method. The synthesis procedures were designed and optimized by the Taguchi experimental design method. Molar concentrations of TEOS, H₂O, NH₄OH, and reaction temperature were chosen as main factors. The results showed that the molar concentration of ammonia is the main factor which affects the particle size of the silica nanoparticles. The chemical structure, size, and morphology of the product were investigated by X‐ray diffraction, Fourier transform infrared spectroscopy, laser light scattering, and scanning electron microscopy. By the optimum conditions of the ultrasound‐assisted sol‐gel method, silica nanoparticles with an average particle size of 13 nm were prepared.     

氟化SiO2纳米颗粒双疏涂层的制备及性能研究

采用氟化硅烷偶联剂对合成的单分散SiO2纳米颗粒进行表面接枝改性,并通过旋涂法将制备的氟化SiO2颗粒沉积在硅晶基板上.采用粒径分析仪、傅里叶变换红外光谱仪(FTIR)、热重分析仪(TG-DTA)、扫描电镜(SEM)和接触角测量仪对氟化SiO2纳米颗粒涂层的表面形貌、化学组成、接枝密度和润湿性能进行分析表征.结果表明:氟化硅烷偶联剂在SiO2纳米颗粒表面的接枝密度为5.94 nm-2;制备的氟化SiO2纳米颗粒薄膜具备微纳米双重复合网络结构,增加了涂层表面的粗糙程度;氟化SiO2纳米颗粒涂层展现出超疏水和强疏油性能,水和柴油在氟化SiO2纳米颗粒薄膜上的接触角分别为158.4°和125.7°.     

Synthesis of sulfated β‐cyclodextrin/cotton/ZnO nano composite for improve the antibacterial activity and dyeability with Azadirachta indica

The sulfated β‐cyclodextrin (sb‐cd) was prepared from β‐cyclodextrin and the sb‐cd was crosslinked with cotton fabric using ethylenediaminetetraacetic acid (EDTA) as crosslinker. After crosslinking, the synthesized ZnO nanoparticles were padded on this fabric surface. Then, the treated fabrics were dyed with neem extract. The synthesized polymer, crosslinked and nanoparticle‐treated cotton fabrics were characterized using fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), particle sized analyzer, and transmission electron microscopy (TEM) studies. The antibacterial test was done against Staphylococcus aureus and Escherichia coli bacterium. The composite coated with neem dyed cotton fabric has exhibited 71% of dye uptake with 2–3 fastness grade and it has 99% of antibacterial efficiency for S. aureus and 97% for E. coli bacterium. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Polyurethaneurea–silica nanocomposites: Preparation and investigation of the structure–property behavior

Nanocomposites consisting of thermoplastic polyurethane–urea (TPU) and silica nanoparticles of various size and filler loadings were prepared by solution blending and extensively characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), thermal analysis, tensile tests, and nanoindentation. TPU copolymer was based on a cycloaliphatic diisocyanate and poly(tetramethylene oxide) (PTMO-2000) soft segments and had urea hard segment content of 20% by weight. TPU/silica nanocomposites using silica particles of different size (29, 74 and 215 nm) and at different loadings (1, 5, 10, 20 and 40 wt. %) were prepared and characterized. Solution blending using isopropyl alcohol resulted in even distribution of silica nanoparticles in the polyurethane–urea matrix. FTIR spectroscopy indicated strong interactions between silica particles and polyether segments. Incorporation of silica nanoparticles of smaller size led to higher modulus and tensile strength of the nanocomposites, and elastomeric properties were retained. Increased filler content of up to about 20 wt. % resulted in materials with higher elastic moduli and tensile strength while the glass transition temperature remained the same. The fracture toughness increased relative to neat TPU regardless of the silica particle size. Improvements in tensile properties of the nanocomposites, particularly at intermediate silica loading levels and smaller particle size, are attributed to the interactions between the surface of silica nanoparticles and ether linkages of the polyether segments of the copolymers.     

Conductive Cotton Fabrics Coated with Myristic Acid/Zinc Oxide Nanoparticles

This research mainly deals with enhancement of electrical conductivity performance of cotton fabrics using zinc oxide nanoparticles. The application of nano-zinc oxide/myristic acid onto 100% cotton plain fabrics was performed by dipping process. The effect of myristic acid and zinc oxide nanoparticles on cotton fabrics was analyzed by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. Electrical conductivity, UV protection performance, and hydrophilic properties of the cotton fabrics were also investigated. The surface resistivity of the cotton fabric noticeably dropped off by applying nano-zinc oxide/myristic acid. Furthermore, electrical conductivity of the coated cotton fabrics was maintained till 15 weeks. Surface hydrophilicity of cotton fabrics decreased with increasing myristic acid content. The changes in decomposition temperatures and crystallinity can be ignorable after application of myristic acid/nano-zinc oxide.     

Development of flame retardancy properties of new halogen‐free phosphorous doped SiO2 thin films on fabrics

In this study, flame retardancy properties of fabrics treated with phosphorous (P) doped and undoped SiO₂ thin films were developed by sol–gel technique. As to this aim, P‐doped and undoped SiO₂ film were coated on cotton fabric from the solutions prepared from P, Si‐based precursors, solvent, and chelating agent at low temperature in air using sol–gel technique. To determine solution characteristics, which affect thin film structure, turbidity, pH values, and rheological properties of the prepared solutions were measured using a turbidimeter, a pH meter, and a rheometer machines before coating process. The thermal, structural, and microstructural characterization of the coating were done using differential thermal analysis/thermograviometry, fourier transform infrared spectroscopy, X‐ray diffractometry, and scanning electron microscopy. In addition, tensile strength, wash fastness, flame retandancy, and lightness properties of the coated fabrics were determined. To compensate the slight loss of tensile strength of samples, which occurred at the treated fabrics with P‐doped Si‐based solutions, the cotton fabrics were coated with polyurethane films during second step. In conclusion, the flame retardant cotton fabric with durability of washing as halogen‐free without requiring after treatment with formaldehyde was fabricated using sol–gel processing for the first time. Moreover the cotton fabrics, which were treated with P‐doped Si‐based solutions and then coated with polyurethane at second step, still has got nonflammable property. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Preparation of dendritic–linear polyether-modified silica sol and its application in coatings

Dendritic–linear polyether-modified silica sol (DLPS) was synthesized using diethylenetriamine, methyl acrylate, epoxy-terminated polyether, triethoxysilane, and silica sol in five steps. The prepared sol was stable and transparent. DLPS was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and particle size distribution analysis. Subsequently, DLPS was examined as a stain-resistant additive in (paint) coatings. The surface of the sample coatings with and without DLPS additive was examined by scanning electron microscopy, energy-dispersive spectrometry analysis, and contact angle analysis. The results showed that the stain-resistant additive appeared on the surface of the coating, which made the surface more compact and hydrophilic. The performance of the stain-resistant additive was examined in commercial outdoor emulsion coatings (WB200). The result showed that the presence of the stain-resistant additive could enhance the stain resistance performance of paint. Furthermore, the stain resistance performance improved with increasing amounts of additive. Specifically, the stain resistance performance of paint improved by 40.63% in the presence of 6 wt% DLPS. Therefore, the current findings demonstrate the importance of DLPS in advancing progress and application in the paint coating industry.     

A novel cyclic copolymer containing Si/P/N used as flame retardant and water repellent agent on cotton fabrics

A novel cyclic-shaped multifunctional copolymer named poly[tetra(tetramethylcyclosiloxyl-piperazin)-phosphinic acid methyl ether] (PNCTSi) was successfully synthesized. Its flame-retardant and hydrophobicity properties on cotton fabrics were investigated. The limited oxygen index (LOI) value of treated cotton fabrics with PNCTSi was up to 29.8%. By vertical burning test, it was found that the treated cotton fabrics have no after-flame and no after-glow. Apparently, more amounts of char were generated and hazardous volatiles distinctly reduce after combustion by thermogravimetric analysis. Besides, Treated cotton fabrics with PNCTSi can give a hydrophobic property, which reach a contact angle of 150°. The surface morphology of treated cotton fabric before and after combustion was analyzed by scanning electron microscopy, after burned, the surface morphology of cotton fiber exhibited more smooth and expanded feature. After washing the cotton fabric for 20 times, the LOI remains at above of 26.0%. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47280.     

Sustained‐release properties of cotton fabrics impregnated with nanotuberose fragrance

Tuberose‐fragrance (TF) loaded polybutylcyanoacrylate nanoparticles were successfully prepared via emulsion polymerization. The nanotuberose fragrance (Nano‐TF) was directly impregnated into the cotton fabrics as an aromatic reagent. Dynamic light scattering and transmission electron microscopy showed that the average size of the spherical Nano‐TF was 202.4 nm. Fourier transform infrared spectroscopy demonstrated that TF was encapsulated into the BCA nanoparticles and that the Nano‐TF was in existence in the cotton fabrics. Thermogravimetric analysis showed that the loading TF content of the Nano‐TF was 50.9% and that 10.02% Nano‐TF had been impregnated into the fabrics. A lot of Nano‐TF was adhered onto the surface of the cotton fabrics after 50 washings, as shown by scanning electron microscopy and gas chromatography/hydrogen flame ionization detection (GC–FID). In addition, GC–FID demonstrated that most aroma compounds of the cotton fabrics impregnated with Nano‐TF only lost less than 20% of their aroma after 60 days of deposition and around 75% of their aroma after 6 h of deposition at 120°C, so they showed better sustained‐release properties than those with TF. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41678.     

Lightweight design of bauxite-SiC composite refractories as the lining of rotary cement kiln using alternative fuels

To meet the demand of energy-saving and adapt to the change from coal to the alternative fuel in the rotary cement kiln, bauxite-SiC refractories were fabricated by the incorporation of silica sol coated lightweight mullite aggregates in order to achieve low thermal conductivity and superior alkali vapor attack resistance simultaneously. Furthermore, the mechanism of resistance to alkali vapor attach was investigated by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results showed that the thermal conductivity of bauxite-SiC specimens decreased gradually with increasing amounts of silica sol coated lightweight mullite aggregates while changes in the alkali vapor attach were not detectable. The shell-covered structure with a silica sol coating on the surface of lightweight aggregates hindered alkali vapor diffusion into the aggregates at high temperature. Bauxite-SiC refractories possessed lower thermal conductivity, superior alkali attack resistance and higher mechanical properties compared with the specimens which contained pristine lightweight aggregates.     

Facile fabrication and modification of polyacrylate/silica nanocomposite latexes prepared by silica sol and silane coupling agent

Polyacrylate/silica nanocomposite latexes were prepared by silica sol and facilely modified with a silane coupling agent γ-methacryloxypropyltrimethoxysilane (KH-570) aimed at reinforcing the interaction between silica nanoparticles and latex particles in a convenient way. The effects of silica sol and KH-570 amounts on the performance of latexes and films are discussed. Particle size and morphology tests demonstrated that the silica nanoparticles could form hydrogen bond interactions between latex particles, and thus influence the rheological properties of latexes. Tensile measurements and SEM photographs showed the reinforcing and toughening roles of silica nanoparticles. SEM images also indicated that the addition of silica sol increased the roughness of films, which resulted in the increase of hydrophilic silanol groups on the film surface and the decrease of water resistance of latex films. The latex films retained good adhesion force, flexibility, and impact resistance even when the silica sol content was as much as 25%. TGA data revealed that the incorporation of silica sol enhanced the thermal stability of the films. After introducing KH-570, the particle size increased with the increase of the amount of KH-570. Moreover, the addition of KH-570 improved the water resistance and maintained other properties of the latex films appropriately.     

Polycarbonate/silica nanocomposite membranes: Fabrication,characterization, and performance evaluation

Polycarbonate/silica nanocomposite membranes at low silica loading were fabricated by solution blending and solvent evaporation technique. The functionalized silica nanoparticles used were synthesized by co‐condensing hydrolyzed tetraethylorthosilicate with 3‐aminopropyl trimethoxysilane in the sol–gel process. The membranes morphology, composition, surface, structure, thermal and mechanical properties were analyzed by the standard characterization techniques. The gas permeation tests were conducted in four‐channel permeation cells. Field emission scanning electron microscopy results reveal that membranes above 3 wt % silica content formed distinguishable voids and agglomerates. Fair distribution of silica nanoparticles and absence of residual solvents were observed by energy dispersive X‐ray and thermogravimetric analysis. Fourier transform infrared spectroscopy spectra confirmed the presence of new functional groups (N? H) and (O? H) bonds. The X‐ray diffraction pattern revealed the polymer‐particle interactions, the formation of rigidified polymer chain, and nanostructured silicon crystals. Further, the thermogravimetric analysis results revealed thermal stability enhancement while differential scanning calorimetry results of increased glass transition temperatures confirmed the presence of rigidified polymer chain. Furthermore, enhancements in mechanical strength of the membranes were observed. Moreover, at all feed pressures, increased CO₂, N₂, and CH₄ gas permeation was observed. At 6 bar feed pressure, the CO₂/N₂ and CO₂/CH₄ ideal selectivities of PC membranes with 3 wt % silica loading have increased from 19.2 to 38.0 and 29.2, respectively. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45310.     

载银介孔氧化硅防污剂的制备及其防污机理研究

采用化学法制备出载银介孔氧化硅(Ag-MSN)粉体,通过扫描电镜(SEM)和透射电镜(TEM)表征纳米材料的微观形貌和尺寸,利用X射线衍射(XRD)确定纳米材料的成分并结合公式确定纳米银的粒径;通过平板培养法和分光光度计法揭示载银介孔氧化硅对于海洋微生物(需钠弧菌)的抗菌效果和机理。将载银介孔氧化硅粉体作为主要颜料与有机硅树脂复合,得到具有一定抑菌性能的涂层。该研究成果将有助于揭示纳米银防污机理,并对绿色海洋防污剂的制备与应用起到重要的促进作用。     

纳米二氧化硅/凹土复合材料的制备以及吸附性能

以硅酸钠为主要原料,用硫酸调节pH,通过液相沉淀法在凹土单晶表面原位生成纳米粒状二氧化硅,制备纳米二氧化硅/凹土复合粉体。利用XRD、TEM、TG-DTG、氮气吸附脱附曲线等方法对复合粉体进行表征。XRD表明,二氧化硅以非晶态的形式包覆在凹土表面,防止了凹土的团聚。TEM照片显示,包覆后的纳米二氧化硅粒径减小,粒度分布均匀,表面光滑。     

The preparation of cotton fabric with super-hydrophobicity and antibacterial properties by the modification of the stearic acid

In this article, the superhydrophobic and antibacterial surface on the cotton fabric were fabricated with the UV curable waterborne coatings, the silver nanoparticles, and the stearic acid. The cotton fabric coated with silver stearate was obtained by immersing in a mixture of sodium hydroxide and then modified by stearic acid. Results showed that the water contact angle on the surface of the fabric was 157.6°. The micromorphology and chemical ingredients of the surface of the coating were studied by scanning electron microscope, Fourier transforms infrared spectroscopy, and X photoelectric spectrometer. Results showed that the immersion resulted in a double decomposition reaction and with the modification of the stearic acid, the silver stearate was formed on the surface, which provided a rough surface required for super-hydrophobicity. And the acid and alkali resistance test, water-resistance test, and antibacterial activity test indicated that the coating had good acid and alkaline resistance, water-resistance, and antibacterial properties.     

APS-silane modification of silica nanoparticles: effect of treatment’s variables on the grafting content and colloidal stability of the nanoparticles

Silica nanoparticles, Aerosil 200, with an average primary particle size of 12 nm were chemically modified by γ-aminopropyltriethoxy silane (APS) via a two-step sol–gel process. Effects of the treatment variables including reaction temperature, water content, and silane concentration on the colloidal stability and the amount of APS grafting on the surface of nanoparticles were studied using thermal gravimetric analysis, diffuse reflectance infrared spectroscopy, and by monitoring the sedimentation behavior of the dispersion of nanoparticles in distilled water as a polar media. Furthermore, the effect of surface modification on the dispersibility of silica nanoparticles in an epoxy novolac coating was evaluated by means of scanning electron microscopy. The results showed chemical interactions between APS and SiO₂ nanoparticles. Also, parameters including treatment at ambient temperature, low level of water, and moderate concentration of silane compound, have a considerable effect on the APS grafting content due to the increase of silane hydrolysis and higher silylation coverage of the nanoparticles.     

Preparation of a halogen-free P/N/Si flame retardant monomer with reactive siloxy groups and its application in cotton fabrics

A novel halogen-free phosphorus-nitrogen-silicon flame retardant monomer with reactive siloxy groups,N-(diphenylphosphino)-1,1-diphenyl-N-(3-(triethoxysilyl)propyl) phosphinamine (DPTA) has been synthesized and was applied to the fire-resistant finishing of cotton fabrics.The molecular structure of DPTA has been well characterized by elemental analysis,FTIR,1H NMR,and 31p NMR spectroscopies.The chemically-grafted cotton fabrics,which were treated with 25 wt％ DPTA,were obtained and confirmed by attenuated total reflectance Fourier infrared spectroscopy (ATR-FTIR).The flame retardancy and thermal property of the treated samples were investigated by limited oxygen index (LOI),vertical flammability test (VFT),thermogravimetric analysis (TGA) and microscale combustion calorimeter (MCC).It is noted that in vertical flammability test,the treated samples extinguished immediately upon removing the ignition source,whereas the untreated one was completely burned out.Furthermore,TGA and MCC tests revealed that the treated samples produced a high char formation and a low heated release during combustion.The surface morphology of the untreated and treated samples and the char residues after LOI tests were observed by scanning electron microscopy (SEM).Therefore,all the results showed that the treated cotton fabrics with 25 wt％ DPTA apparently improved the fireresistant and thermal performances.     

A coloured polyester fabric with antimicrobial properties conferred by copper nanoparticles

In this study, we aimed to produce a coloured polyester fabric through the in situ sonosynthesis of copper nanoparticles using copper sulphate, hydrazine, sodium hydroxide and polyvinylpyrrolidone. The treated fabrics were characterised by X‐ray diffraction, field emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy and elemental mapping. Moreover, mechanical properties, wettability and antibacterial/antifungal activities of the treated fabrics were evaluated. Central composite design based on the response surface methodology was used to study the effect of copper sulphate, hydrazine hydrate and sodium hydroxide on the weight gain and colour of the treated fabrics. In addition to their roles as reducing agents, hydrazine and sodium hydroxide were responsible for the simultaneous aminolysis and hydrolysis of polyester, increasing the adsorption of nanoparticles on the surface. According to the results, the reddish brown samples treated with copper nanoparticles showed excellent antibacterial and antifungal efficiencies, improved tensile strength and decreased wettability.